Brown sulfur dye and process of making same.



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TO LEOPOLD CASSELLA &: (70., OF SAME PLACE.

BROWN SULFUR DYE. AND PROCESS OF MAKING SAME.

SPECIFICATION forming part of Letters Patent No. 660,067, dated. October 16, 1900.

Application filed August 29,1899.

To all whom it mayconcerm,

Be it known that I, ARTHUR WEINBERG, a citizen of Prussia, and a. resident of Frankfort-on-the-lllain, Hesse -Nassnu, Germany, have invented new and useful Improvements in Brown Dyes and Processes of MakingSame, of which-the following is a specification.

This invention relates to the manufacture of a. new brown coloring-matter which fixes itself on the vegetable fiber \vithoutthe aid of a mordant. v

The process of the manufacture of my new dye consists in the following operations: First, m-amido-o-cresol is heated together with dinitro-chlorhenzene and uneutrsliziug agent, such as carbonate of lime or acetate of soda; second, the dinitrophenyl-oxytolyl-muin thus produced is treated with nitricneid and trans formed hereby into a polynitro derivative; third, this polynitro com pound is heated with sulfids and sulfur.

The following example will illustrate the manner in which my invention can be carried out:

Example: The aqueous solution of ten kilos p-amido-o-cresol (CH OH: Nl'l l 2 4 is boiled during sereral hours with 16.5 'kilos dinitrochlorbenzene and fifteen kilos acetate of sodium. Ten kilos of the dinitro-phenyl- 3o. oxy tolyl-amin thus obtained are dissolved in one hundred kilos sulfuric acid of 66 Baum and at a temperature of about 5 centigrade. Ten kilos of a mixture of nitric acid and sulfuric acid, containing 4,4 kilos HNO are slowly introduced. After all nitric acid has been added the nitration is kept standing for several hours and then diluted with ice. Tet- ,ranitro-oxyphenyl-tolyl-amin separates in the form of an orange-colored precipitate which 0 is filtered off, washed, and dried. Ten kilos of this tetrnnitro-oxyphenyltolylzzunin are Serial lilo. 728,864- (Specimens) hosted with sixty kilos sulfid of sodium and fifteen kilos'sulfur and some water up to about 1 .20 centigrade. The thus-obtained coloring-matter dyes unmordamcd cotton brown shades. By treating those dyeings with metullic salt s, especially copper salts and bichromates, the shades turn to a more yellowish brown.

The dyestuff further possesses the very re- 5'0 markuble property, which has not yet been stated in the class of colors it belongs to, of being transformed by nitrous acid in to a diazo compound, and can therefore be developed on the fiber by the known diazol-izing process.

What I claim as new, and desire to secure by Letters Patent, is-

' 1. The new substantive brown dyestuff which is obtained in the form of black lumps or black powder, by heating: polynitro-oxy- 6o pheuyl-tolyl-nmin with sullids and sulfur, which dissolves easily in water with a darkbrown color, being precipitated from this solution by acids, dyeing u'umordanted cotton brown shades, which can be diazotized and developed on the fiber, substantially as described.

2. The herein-described process for the manufacture of a, substantive brown dyestutf ARTHUR WEINBERG.

Witnesses: I

JEAN GRUND,

CARL GRUND.

which process consists in heating amido-cre- 7o 

